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The Pioneer 10 Probe Plaque is an anodised aluminium plaque that was placed on the Pioneer 10 spacecraft, launched in 1972.
The plaque was designed to transmit information about the Earth in case the probe was encountered by an extraterrestrial civilisation.
The plaque contains several elements, such as an image of a human being, a representation of the solar system and a description of the Earth's location in the Milky Way.
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The idea behind the plaque was to show our existence and to provide a basic form of communication with possible extraterrestrial beings.
Although the Pioneer 10 probe has travelled beyond our solar system, it is unlikely that the plaque will be found by any alien civilisation anytime soon.
The probe is currently more than 8 billion kilometres away from Earth, heading towards the red giant star Aldebaran in the constellation Taurus, where it will arrive in 1.69 million years.
Its last transmission was on 23 January 2003 when it was twelve billion kilometres from Earth.
